This invention generally relates to computers. In particular, it pertains to a computer which not only has audio signal input/output capability but also employs a multi-window display system.
The computer industry has continuously introduced various multi-media computers, many of which have audio signal input/output capability together with animated image display capability. Such a multi-media computer generally employs a multi-window display system to display different information simultaneously and independently on different areas called windows resulting from splitting a display screen, and plural icons are usually displayed so that an operator can activate any one of them using a device called a mouse.
In a conventional multi-window display system, a window, in which information that is not currently referred to by an operator is being displayed, can be closed to display an alternative to that window, i.e., an icon image with a smaller area. Thus, the area of a screen is effectively used. When closing an unnecessary window to display it as an icon image, a pattern to be applied to an icon image is read from a corresponding memory for display. Thereafter, such an icon image is displayed as a still image keeping the same pattern until it is activated to open a window.
There are certain types of icon images capable of changing their patterns whilst being displayed on the screen of a display unit. For example, when an icon image is selected by an operator with a mouse for initiating input operations, such an icon image changes its pattern so as to indicate its current status of "being selected". For the case of an icon image of a clock, such an icon image can change its pattern so as to show time. For the case of an icon image indicative of whether an electronic mail is received, it can change its pattern when a monitoring system detects the receipt of an electronic mail. However, it will take at least a period of some several seconds for an icon image to be able to change its pattern. Any shorter period than that results in disadvantageously increasing the burden to be handled by a CPU. This prevents conventional techniques from producing an icon image which shows no awkward movements.
There are several drawbacks presented by conventional multi-media computers.
For example, with a first piece of information being displayed in a first window, and with a first audio signal corresponding to the first piece of information being output through a loudspeaker in the form of a sound, if the first window is closed and displayed as an icon image in order that a second piece of information is displayed in a second window, both the first and second audio signals will be output in the form of a sound at the same time. This causes hearing confusion to an operator.
Meanwhile, if an audio signal corresponding to information of a closed window in the form of an icon image is stopped, that is to say, if such an audio signal is not output currently through a loudspeaker in the form of a sound, this allows an operator to clearly hear a sound corresponding to information displayed in a newly opened window. However, this presents a problem that it is most hard for an operator to visually realize that there exists a concealed sound behind a closed window now in the form of an icon image, since such a closed window is displayed as a still image with no movements.